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1.
川东红池坝地区红三叶(Trifoliumpratense)和鸭茅(Dactylisglomerata)人工草地土壤和植物营养元素的含量特征如下:(1)土壤中的元素含量以铁、钾和镁较高,钠、钙、氮、锰和磷较低,硫、锌、硼、铜和钼微少;(2)从元素的富集特征来看,该区土壤中的钙、硫为重度淋溶元素,钾、磷、镁、锌、钠为中度淋溶元素,铁、铜属轻度淋溶元素,锰属富集元素;(3)根据元素的生物吸收系列,红三叶属氮-钙型植物,鸭茅属氮-钾-磷型植物。(4)两种牧草的生物吸收系数,均以钙、硫、磷较高,钠、铁较低,其余7种元素介于二者之间。  相似文献   

2.
京郊耕地碳酸盐褐土小麦、大麦、玉米、高梁、花生五种农作物氮及灰分元素生物循环的研究结果表明:1.不同作物存留、归还、吸收不同元素数量的差别很大。豆科作物花生以对钙、镁吸收量大为其显著特征;禾本科作物吸收较高数量硅、铁、铝、锰、钠。在四种禾本科作物中,高梁吸收较高数量氮、磷,钾、钙、镁、硅,大麦吸收较高数量钠、硫和锰。2.不同作物以根、茬形式对11种元素和灰分向土壤中的归还有三种情况:1)低度归还类型:氮磷钾,归还比例一般低于10%;2)中度归还类型:镁钙硫硅钠和灰分,归还比例介于10—30%;3)高度归还类型:铁铝和锰,归还比例一般为30%。 3.不同农作物生物循环特点对研究农田生态系统元素平衡、耕地土壤肥力变化和形成过程以及施肥、耕作制度改革,都有重要意义。  相似文献   

3.
福建九龙江口秋茄红树林的生物量和六元素的累积与循环   总被引:2,自引:0,他引:2  
本文讨论了20年生人工秋茄群落的生物量和氮、磷、钾、钠、钙、镁6种元素的累积及生物循环。结果表明,秋茄现存量为162.63吨/公顷,其中地上部为93.37吨/公顷,地下部为69.26吨/公顷;地下部占总量的42.59%。该群落含有氮、磷、钾、钠、钙、镁元素,总量分别为935.47、112.02、531.97、2100.35、772.91和526.57公斤/公顷;其中6元素生物循环中,年吸收量分别为213.31、21.75、109.15、353.50、174.86和89.30公斤/公顷,年归还量分别为129.15、10.84、59.37、160.18、103.28和40.42公斤/公顷,年存留量分别为83.79、10.91、49.78、193.32、71.58和48.88公斤/公顷;群落中6元素的周转期分别为7、10、9、13、8和13年。元素的周转期较陆生森林为短,是红树林的一个特点。  相似文献   

4.
人工油松林的化学元素特征   总被引:8,自引:0,他引:8  
28年生人工油松林的建群种——油松各器官化学元素浓度由叶、小枝、枝和树干逐渐下降。叶内元素浓度高低,以碳、氮、钙、钾、镁、磷为序。地下部分细根较粗根的元素浓度为大。灌木的化学元素的共同特点是碳含量最高,其次为氮、钾和钙。灌木叶片中的元素浓度大于茎。草本植物地上部分元素浓度明显低于灌木叶。灌木根系内化学元素浓度均低于它的地上部分。枯枝落叶的化学成分与活的枝、叶相比,铁的浓度显著增加,其次为铝,其他元素的浓度或多或少有所下降。在人工油松林各层次植物中,以碳素积累量最高,其次为钙和氮。元素的存留量仍以碳素为高,其次在乔木层中存留量以钙较大,在灌木层中以氮、钾较高。元素的年归还量除碳以外,钙较高,钾、磷较低。人工林的吸收量/土壤贮量的比值,以钾和磷较高。土壤中代换性钾、磷的贮量相对不大,为促进人工林生长,增施磷肥和钾肥将是有效的。  相似文献   

5.
川东地区池坝地区红三叶(Trifoliumpratense)和鸭茅(Dactylisglomerata)人工草地土壤和植物营养元素的含量特征如下;(1)土壤中的元素含量以铁,钾和镁较高,钠,钙,氮,锰和磷较低,硫,锌,硼,铜和钼微少;(2)从元素的富集特征来看,该区土壤中的钙,硫为重度淋溶元素,钾,磷,镁,锌,钠为中度淋溶元素,铁,铜属轻度淋溶元素,锰属富集元素;(3)根据元素的生物吸收系列,红三  相似文献   

6.
红海榄红树林的氮、磷积累和生物循环   总被引:15,自引:0,他引:15  
尹毅  林鹏 《生态学报》1993,13(3):221-227
本文讨论广西山口英罗湾中红海榄群落的氮、磷含量及其生物循环。结果表明,红海榄群落现存量中,含氮、磷总量分别为221.15和13.27g/m~2。其中地上部分别为134.90和8.73g/m~2;地下部分别为86.25和4.54g/m~2。该群落的氮、磷元素生物循环中,年吸收量分别为12.91和1.27g/m~2,年存留量分别为7.04和0.65g/m~2;年归还量分别为5.86和0.61g/m~2。富集率分别为1.11和1.60。群落各组分的氮含量均大干磷含量;周转期氮需38a,比磷(22a)慢。  相似文献   

7.
本文是福建九龙江口红树林生态系统研究的一个部分,主要讨论20年生秋茄群落的氮、磷含量及其生物循环。试验结果表明:秋茄群落现存量中,含有氮、磷总量分别为935.47和112.02公斤/公顷。其中地上部分别为582.26和70.47公斤/公顷,地下部分别为353.21和41.55公斤/公顷。该群落氮、磷元素生物循环中,年吸收量分别为213.31和21.75公斤/公顷;存留量分别为83.75和10.91公斤/公顷;归还量分别为129.52和10.84公斤/公顷。它们的氮含量均大于磷含量,周转期氮需7年比磷需10年为快。  相似文献   

8.
哀牢山北部木果石栎林的元素积累及循环   总被引:6,自引:1,他引:5  
根据对哀牢山北部徐家坝地区木果石栎林化学元素的吸收、分布及其生物循环的研究结果表明,碳素在树干中含量最高,而其它元素的含量均以叶片最高,枝和根其次,树干最低。该森林群落中碳、氮、磷、钾、钙、镁、锰、钠、铝和铁元素的积累量达260346kg/hm^2,其中乔木层的元素积累量占该群落元素总积累量的98.5%,灌木层和草本层的元素积累量仅分别占1.3%和0.2%。在该群落中各元素的积累量以碳>钙>氮>钾  相似文献   

9.
本文是福建省九龙江口红树林研究的一部分,主要讨论20年生秋茄(Kandelia candel) 群落氯元素的累积及其生物循环。试验结果表明,秋茄群落现存量中含有氯总量3864.13公斤/公顷:其中地上部为1287.75公斤/公顷,地下部为2576.38公斤/公顷。该群落氯元素生物循环中年吸收量为626.57公斤/公顷,归还量为271.31公斤/公顷,存留量为355.26公斤/公顷,周转期需14年。  相似文献   

10.
 本文在鼎湖山亚热带季风常绿阔叶林黄果厚壳桂、鼎湖钓樟群落生物生产量研究结果的基础上,测定了群落主要植物20种44株各部分器官的含氮量,研究了氮素在植物中的分布、积累和生物循环。结果表明,植物群落总贮氮量(kg·ha-1)是1021.14,其中乔木层986.64,灌木层5.57,草本层9.58,层间植物19.35;群落中植物吸收氮量(kg·ha-1·yr-1)为215.52,归还量172.19,存留量43.33。循环系数为0.80,周转期5.9年。氮的归还量大,循环系数高,周转期短,反映了南亚热带地区物质循环快速旺盛的特点,也表明了群落处于生长盛期。  相似文献   

11.
 本文用盆钵试验研究京郊石灰性草甸土冬小麦养分生物循环的结果表明:小麦对不同养分吸收、携出和归还数量的差异很大。根据随籽粒携出和以根茬归还的比例特点,可将养分划分为三种类型:1)低归还高携出型(N、P、K);2)低携出高归还型(Ca、Fe);3)中归还中携出型(Mg、Mn、Cu、Zn)。施锰增加植株对氮和锰的吸收及钾和锰随籽粒的携出;施锌则降低植株对锰的吸收和随籽粒携出的钾、钙、镁、铁、锰量。锰肥和锌肥有拮抗作用。  相似文献   

12.
杉木成熟林乔木层营养元素生物循环的研究   总被引:3,自引:1,他引:2       下载免费PDF全文
广西龙胜县里骆林区25—28年生杉木林乔木层平均每年吸收10种营养元素的总量为139.278kg/ha,其中19.5%存留在立木上,48.1%通过凋落物、32.4%通过降水淋溶归还土壤。N、Mg、S、Mn、Zn、B的归还比都超过0.8;P、K、Ca的归还比为0.72一0.74;Cu的则低于0.7。影响杉木林乔木层营养元素循环的主要因素是土层厚度、土壤养分的浓度和林分测树因子。  相似文献   

13.

Background and Aim

Biotic and abiotic factors contribute in shaping the distribution through the soil profile of elements released by mineral weathering; among them, leaching and biocycling dominate in temperate environments. We evaluated if the intensity of leaching and biocycling of nutrients can be modulated by element deficiencies linked to the abundance of serpentine in the soil parent material, i.e. if the most deficient elements are more efficiently retained.

Methods

We selected twelve poorly developed soils from Northern Italian beech stands, with variable amounts of serpentinites in the parent material, and determined total and exchangeable Ca, Mg and K, as well as an index of abundance of serpentine minerals.

Results

The total element content depended on the abundance of serpentines, while only exchangeable Mg was related to the parent material. The vertical trend of Ca and K indicated the role of biocycling in all soils, but the relative availability of Ca (ratio between exchangeable and total content) was much higher in the top horizons of serpentine-rich soils.

Conclusions

The different element availability among soils suggested that the vertical distribution of available elements was linked to the parent material and that losses were limited in serpentine-rich soils, probably because plants take up the deficient elements as soon as they are released from litter and thus limit their leaching in deeper soil horizons.  相似文献   

14.
van Praag  H.J.  Weissen  F.  Dreze  P.  Cogneau  M. 《Plant and Soil》1997,189(2):267-273
In the Ardennes, spruce decline is correlated with Mg deficiency caused by acid rain leaching of soil nutrients, associated with solubilization of Al-containing soil minerals. Laboratory experiments were carried out to measure the uptake and translocation of 45Ca and 28 Mg by intact roots of spruce seedlings in solutions containing various amounts of added AlCl3. Translocation rates in the various organs of the seedlings were higher for magnesium than for calcium. A 1 mt M Al nutrient solution had a much stronger inhibitory effect on uptake and translocation of Mg than it had on Ca. These rate differences result largely from differences in the chemical characteristics of these two elements.  相似文献   

15.
氮沉降对半干旱草原植物群落钙浓度的影响 钙(Ca)是植物生长所必需的营养物质,牧草中钙的含量对反刍动物的饲粮和健康具有重要意义。目前,关于氮沉降增加是否改变牧草的Ca浓度仍不是十分清楚。我们于2008–2015年在中国北方半干旱草原开展了氮沉降速率增加实验,测定了不同氮处理下每个样方内所有植物的Ca浓度,并且 根据各样方内每个物种的Ca浓度及其相对生物量,计算出功能群水平和群落水平的植物Ca浓度。研究结果表明,尽管物种水平和功能群水平的Ca浓度对氮沉降表现为负响应,但群落水平Ca浓度在整个氮添 加速率梯度上保持稳定。由于杂类草Ca浓度显著高于禾草,杂类草相对生物量的增加抵消了物种水平和功能群水平Ca浓度对氮沉降的负响应。另外,群落Ca库对氮添加速率表现为正饱和响应,且阈值为10 g N m−2 yr−1。本研究表明了氮沉降背景下植物相对生物量的变化对调控牧草Ca浓度和储量具有重要作用。  相似文献   

16.
Rineau F  Rose C  Le Thiec D  Garbaye J 《Fungal biology》2010,114(11-12):1007-1014
Liming is a forest practice used to counteract forest decline induced by soil acidification. It?consists of direct Ca and Mg input in forest soil and restores tree mineral nutrition, but also causes drastic changes in nutrient availability in soil. Ectomycorrhizal (ECM) fungi significantly contribute in nutrient uptake by trees, and can recover them through organic acid secretion or through enzymatic degradation of organic matter. The symbiotic fungi use their extraradical mycelium for nutrient uptake, and then store them into the ECM mantle. In this study we measured how liming influences element contents in the mantle of Lactarius subdulcis ECMs, an abundant and particularly active in oxalate and laccase secretion in beech stands. For this purpose we used SEM observation coupled with energy- (EDX) and wavelength-dispersive-X-ray microanalyses (WDX). Results showed that ECM mantles of this species presented significantly higher Ca, Mg, Mn, K, Si, Al and Fe contents in limed plots. The nutrient amounts of L. subdulcis ECMs were significantly different between individuals for all the elements, showing a differential storage ability between individuals. The storage role of the ECM mantle can be interpreted in two different ways: i) a detoxification role for Al or heavy metals and ii) an increased potential nutrient resource by the fungus, which can benefit the tree.  相似文献   

17.
TYLER  G.; ZOHLEN  A. 《Annals of botany》1998,81(3):455-459
Mineral nutrients of seeds constitute a significant source ofessential elements to seedlings and developing individuals ofvascular plants. In spite of their potential ecological significance,seed nutrient pools have attracted little attention with respectto calcifuge–calcicole behaviour of plants. The objectivesof this study were, therefore, to compare concentrations of13 macro- and micronutrients (K, Rb, Mg, Ca, Mn, Fe, Co, Cu,Zn, Mo, B, P and S) in seeds and leaves of 35 mainly herbaceousvascular plant species growing on both limestone (calcareous)and silicate (non-calcareous) soils. Concentrations of Rb andCo in seeds of plants originating from limestone soils were,on average, about half of those from silicate soils. Concentrationsof Mn, Mg, Zn and P of seeds were, or tended to be, lower orslightly lower in limestone-soil plants, whereas mean Ca andMo concentrations were higher. Comparing seed and leaf concentrationsof the same species from limestone and silicate soils generallydemonstrated a high P enrichment ratio, but a particularly lowK enrichment ratio in seeds, valid for both types of soil. Itwas also apparent that Fe and Mn, micronutrients which are lessreadily solubilized and taken up by plants on limestone soils,had significantly higher seed:leaf concentration ratios in plantsfrom limestone than from silicate soils, whereas the oppositewas true for Ca. This indicates a ‘strategy’ tosatisfy the demand of seedlings for elements which are lessreadily available in the soil.Copyright 1998 Annals of BotanyCompany Seed, leaf, plant, nutrient, content, calcareous, silicate, acid, soil.  相似文献   

18.
芒萁群落中营养元素的循环特点   总被引:3,自引:0,他引:3  
陈建  钟章成 《生态学报》1991,11(4):299-306
  相似文献   

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